Multiphase palladium-based nanocatalysts provide more active sites for electrocatalytic reactions due to their abundant interfacial defects, thus effectively promoting their electrocatalytic efficiency. However, the preparation and synthesis of such multiphasestructure palladium-based catalysts and the fine regulation of their compositions are still a great challenge. In this work, multiphase wavy PdSnP nanowire catalysts were obtained by doping PdSn nanocatalysts with phosphorus atoms. The nonmetallic phosphorus atom can turn the crystal phase into the amorphous phase when it enters the lattice of PdSn nanowire catalysts. Therefore, a crystalline and amorphous multiphase structure can be constructed in wavy PdSn nanowire catalysts by controlling the doping of phosphorus atoms carefully. Due to atoms with abundant interfacial defects on their surface, the multiphase wavy PdSnP nanowire catalysts showed enhanced catalytic efficiency in the electrocatalytic oxidation reactions of methanol and ethanol. In the methanol oxidation reaction, the mass and specific activities of the multiphase PdSn 0.41 P 0.093 nanocatalyst are 4617.2 mA mg Pd −1 and 20.89 mA cm −2 , respectively, and in the ethanol oxidation reaction, the mass and specific activities of the multiphase PdSn 0.41 P 0.093 nanocatalyst are 4453.1 mA mg Pd −1 and 20.14 mA cm −2 , respectively. This study provides a reference for the design and synthesis of high-efficiency electrocatalysts for methanol and ethanol oxidation.